CONCORD -- When the classroom discussion veered into the topic of illegal immigration last year, Moises Roberto De Leon waited several minutes before wading into the heated debate. When he finally spoke, the De La Salle High School student revealed a secret known only to his closest family and friends.

"I'm in the same situation," he remembers telling his classmates, revealing that his parents brought him to the United States illegally when he was 2 years old. "Many kids are brought here without their knowledge. They shouldn't suffer for what the parents did."

The 18-year-old senior at the all-boys Catholic school is one of thousands of undocumented students who will graduate from a California high school this spring. December's congressional defeat of the Dream Act, a federal bill that laid down a path to citizenship for those brought to the country illegally as children, was a setback to students such as De Leon. But as the public debate quieted, De Leon went on with his life: studying, volunteering at a community center, applying to colleges and searching for the means to afford one of them.

"You never know," said De Leon, who wants to be a biochemist. "All these people could give back something that might help the U.S."

While the youth-driven movement to pass the Dream Act failed in its objective last year, the political fight raised awareness about the estimated half-million Californians younger than 30 years old who could have benefited from the legislation if they graduated high school and pursued higher education or military service. The movement also fortified networks and information-sharing between those students and concerned educators.

"They probably never realized there were people worried about them," said Antioch Councilwoman Mary Rocha, who participated in a conference last week for local students who are living in the country illegally. "No one ever gives them information."

At the Saturday gathering at Diablo Valley College, more than 100 undocumented students and a few dozen parents talked about some of their challenges and how to overcome them. Co-sponsored by the Pleasant Hill college, Pittsburg's Los Medanos College and a group called United Latino Voice of Contra Costa County, of which Rocha is a member, the event was the first of its kind in the county.

"I met other people in the same situation I am," De Leon said.

While his father, a scaffold builder, and his mother, a stay-at-home mom, have strongly supported his education, De Leon said he was lacking expert knowledge about the difficulties he will have in applying for college and getting a job when he does not have legal residency. De Leon had kept his problems to himself because few students at his private high school are illegal immigrants, and if they are, they don't share it. De Leon's two younger siblings also do not share his obstacles: Both are citizens because they were born in the United States.

De Leon, however, was already luckier than many of the students he met over the weekend. His parents are on the road to becoming legal residents and eventually citizens, which means that sometime in his 20s, he should be able to join them, he said.

"These students are asking a lot of questions. Many of them hear the rumors -- chismes, as they call them -- about what they can and cannot do," said Walnut Creek lawyer Nicolas Vaca, who led a workshop Saturday on immigration rights. Vaca's was the second most popular talk at the student conference. The most popular was about how to afford college.

Vaca asked his classroom full of students, "Who was brought here as a kid?" Most of them raised their hands.

"For the first time, they're seeing, hey, look, people care that we're getting an education," Vaca said. "This is something we needed for a long time. They're getting information that's going to help them."

Aware of the sensitivity of the subject matter, and the fear that some students have of making their immigration status known, organizers advertised their event mostly through word of mouth. U.S. Immigration and Customs Enforcement does not specifically target students for arrest and deportation, but some are picked up in other enforcement operations, and others are delivered to the agency's custody after a run-in with local police.

Latino youths in the past decade became the majority of the under-18 population in Contra Costa County and statewide, according to 2010 census data released this month, but just a fraction of those students are undocumented. A study last year by the Migration Policy Institute estimated that about 7 percent of Latino young people in California do not have legal residency.

Most attendees at Contra Costa's conference were born in Latin America, but Asian-Americans also attended the workshops, a reflection of the diversity of the Bay Area's undocumented population. Students who are illegal immigrants are a minority, but one that society would be ill-advised to abandon, Rocha said.

"The community at large is much richer if we educate our students who are not here legally," Rocha said.

Since 2001, California has allowed undocumented students to pay in-state tuition at public colleges, saving those students thousands of dollars a year. A state Supreme Court ruling last year affirmed the constitutionality of the legislation, known as AB540. Assemblyman Tim Donnelly, R-Twin Peaks, has introduced a bill that would repeal AB540. Another lawmaker, Assemblyman Gil Cedillo, D-Los Angeles, seeks to expand the opportunities provided to illegal immigrant students with a bill called the California Dream Act, which would allow those students to compete for financial aid.